Scholarlink

<p>Laser-directed energy deposition (LDED) of Ti6Al4V offers significant potential for fabricating high-integrity components; however, the synergistic effects of laser power on defect formation, microstructure evolution and mechanical properties remain inadequately understood. This study systematically investigates the influence of laser power (500–1100&#xa0;W) on the melt pool characteristics, phase composition, grain morphology, and mechanical properties of Ti6Al4V fabricated by LDED. Results indicate that laser power critically governs energy input, solidification kinetics, and resultant phase morphology. An optimal laser power of 700&#xa0;W produces fine interlaced <i>α</i>′-Ti laths within prior <i>β</i> grains, minimal porosity (0.15%), and superior mechanical performance: microhardness of 480.7 ± 10.72 HV<sub>0.2</sub>, ultimate tensile strength of 887.23 ± 8.5&#xa0;MPa, and uniform elongation of 15.2 ± 0.5%. In contrast, lower power (500&#xa0;W) induced lack-of-fusion defects and irregular pores, degrading properties, while higher power (≥ 900&#xa0;W) promoted coarse <i>α</i>′ colonies, spherical pores, and brittle fracture. Kernel average misorientation (KAM) mapping identified strain localization along colony boundaries as the dominant crack-initiation mechanism. This study establishes a quantitative process–structure–property relationship and provides a reliable basis for manufacturing high-performance Ti6Al4V components via LDED.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Optimization of laser power in laser-directed energy deposition of Ti6Al4V for superior strength–ductility synergy

  • 期刊论文

  • 发表日期：

    2026年7月20日

查看全文
  • ShengHao Hu,
  • ChengFang Chai,
  • Shuai Guo,
  • FengXian Li,
  • YiChun Liu,
  • JianHong Yi,
  • Jie Yu,
  • Jürgen Eckert

摘要

Laser-directed energy deposition (LDED) of Ti6Al4V offers significant potential for fabricating high-integrity components; however, the synergistic effects of laser power on defect formation, microstructure evolution and mechanical properties remain inadequately understood. This study systematically investigates the influence of laser power (500–1100 W) on the melt pool characteristics, phase composition, grain morphology, and mechanical properties of Ti6Al4V fabricated by LDED. Results indicate that laser power critically governs energy input, solidification kinetics, and resultant phase morphology. An optimal laser power of 700 W produces fine interlaced α′-Ti laths within prior β grains, minimal porosity (0.15%), and superior mechanical performance: microhardness of 480.7 ± 10.72 HV0.2, ultimate tensile strength of 887.23 ± 8.5 MPa, and uniform elongation of 15.2 ± 0.5%. In contrast, lower power (500 W) induced lack-of-fusion defects and irregular pores, degrading properties, while higher power (≥ 900 W) promoted coarse α′ colonies, spherical pores, and brittle fracture. Kernel average misorientation (KAM) mapping identified strain localization along colony boundaries as the dominant crack-initiation mechanism. This study establishes a quantitative process–structure–property relationship and provides a reliable basis for manufacturing high-performance Ti6Al4V components via LDED.